Break-away trolley hook

ABSTRACT

A hook pivotally mounted between two parallel side plates may be caused to rotate by loads which hang eccentric of the pivot point, to cause the load to slide off the hook. The hook is fixedly held in a first position by an arm which is pivotally mounted between the side plates. one end of the arm abuts the hook in the region between the hook&#39;&#39;s pivot point and the load such that the hook is unable to rotate about its pivot point towards its position of stable equilibrium, and this causes the load to be retained on the arm. The arm may be pivoted out of contact with the hook by pulling downwardly on a pull rope which is mounted at the opposite end of the arm, by tripping the arm, or by any power operated device. Thus free from constraint, the hook rotates about its pivotal point under the force of the load until a position of stable equilibrium is reached. The equilibrium position is such that the load will slide off the hook. The arm has a spring which causes it to return to its original position and forces the hook to return to its load support position.

United States Patent [191 Jaarsma 1 BREAK-AWAY TROLLEY HOOK [76] Inventor: Robert J. Jaarsma, c/o Natmar Inc.,

4026 Cherry St., Cincinnati, Ohio [22] Filed: Apr. 25, 1974 [21] Appl. No.: 463,968

[52] U.S. Cl 24/230.5 SS, 198/177 R, 294/83 R [51] Int. Cl. 865g 17/20, B66c 1/34 [58] Field of Search 294/83 R, 85; 198/177 R; 214/380, 381; 24/230.5 R, 230.5 SS, 230.5

SA, 241 P, 241 SB [56] References Cited UNITED STATES PATENTS 644,063 2/1900 Deyoe 294/83 R 1,368,647 2/1921 Myers 294/83 R 2,341,876 2/1944 Masterson 294/83 R Primary ExaminerDonald A. Griffin {57] ABSTRACT A hook pivotally mounted between two parallel side plates may be caused to rotate by loads which hang eccentric of the pivot point, to cause the load to slide off the hook. The hook is fixedly held in a first position by an arm which is pivotally mounted between the side plates. one end of the arm abuts the hook in the region between the book's pivot point and the load such that the hook is unable to rotate about its pivot point towards its position of stable equilibrium, and this causes the load to be retained on the arm. The arm may be pivoted out of contact with the book by pulling downwardly on a pull rope which is mounted at the opposite end of the arm, by tripping the arm, or by any power operated device. Thus free from constraint, the hook rotates about its pivotal point under the force of the load until a position of stable equilibrium is reached. The equilibrium position is such that the load will slide off the hook. The arm has a spring which causes it to return to its original position and forces the hook to return to its load support position.

10 Claims, 2 Drawing Figures 1 BREAK-AWAY TROLLEY HOOK BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a break-away hook device wherein loads carried by the hooks may be quickly and easily discharged. It has particular utility in systems such as conveyor systems wherein trolleys employ hooks to convey loads.

2. Description of the Prior Art Releasing hooks are known in the prior art. Thus Porter US. Pat. No. 905,576 discloses a releasing hook wherein a single spring is operatively positioned between a pivotally mounted latching member and a hook member. A load supported on the hook causes the hook to pivot about its axis, thus allowing the load to slide off when the latching member is activated. The activation of the latching member and the pivotal motion of the hook compress the spring, which generates a force that causes the hook and latching members to return to their original locked position. This system functions in a considerably different manner than that of the subject disclosure.

The following patents disclose releasable hooks which do not have return mechanisms but must be manually returned to a support position.

Ruggles L62 l .604 Lowery 2,907,600 H aviside 906. 226

SUMMARY OF THE DISCLOSURE Although the prior art discussed above discloses various configurations of break-away hooks, all are more complex and require rather detailed structuring of their various elements for a proper functioning of therespective devices.

The device of this invention comprises a hook which is pivotally mounted between two parallel side plates and which may be caused to rotate because loads hang eccentric of the pivot point. This causes the load to slide off the hook. The hook is fixedly held in a first position by an arm which is pivotally mounted between the side plates. Specifically, one end of the arm abuts the hook in the region between the hooks pivot point and the load such that the hook is unable to rotate about its pivot point towards its position of stable equilibrium, and this causes the load to be retained on the arm. The arm may be pivoted out of contact with the hook by pulling downwardly on a pull rope which is mounted at the opposite end of the arm by tripping the arm, or by any power operated device. Thus free from constraint, the hook rotates about its pivotal point under the force of the load until a position of stable equilibrium is reached. The equilibrium position is such that the load will slide off the hook. The arm has a spring which causes it to return to its original position and forces the hook to return to its support position. Thus a simple break-away trolley hook is disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view of the elements comprising the device of the invention; and

FIG. 2 is an isometric view of the assembled device shown in FIG. 1. used in a conveyor system.

DETAILED DESCRIPTION The various elements comprising the device of the invention and the manner in which they interact are shown in FIG. 1. The frame assembly 10 for the breakaway hook of the invention comprises upper plate 11, and similar side plates 12 and 13. The side plates each define a plurality of corresponding apertures. Thus side plate 13 defines apertures 14 through 18, and side plate 12 defines correspondingly located side plates 14' through 18.

Hook [9 comprises three integral sections 20. 21 and 22. Sections 20 and 22 each form obtuse angles with section 21, and section 22 is somewhat longer than section 20, with section 21 being the shortest in length. Pin 23 is received by apertures 14 and 14' through aperture 24, and thereby pivotally supports hook 19 between the side plates. Pins 25 and 26 are also mounted between the side plates. Pin 25 limits the clockwise rotation of hook 19 about pin 23, and pin 26 limits the counterclockwise rotation of hook 19 about pin 23.

Trip lever 43 is pivotally supported between the side plates by pin 27 which extends through aperture 29 defined by the trip lever. One end of compression spring 46 is supported between the side plates by pin 28, and the other end is attached to the cotter pin 30 which extends through hole 31 to the bottom of the trip lever. and is secured thereto. A handle 32 or pull rope or the like is attached to the end of trip lever 43 which extends outside the area defined by the side plates.

The operation of the break-away hook described above according to the invention may be explained with reference to FIGS. 1 and 2. FIG. 2 shows a conveyor system wherein a plurality of trolleys 40 are transported in a conveyor system. A frame assembly 10 as described above is attached to each trolley, and a load 41 is carried thereby by hook 19. In order to retain the load 41 on hook 19, trip lever 43 is set such that its end 33 abuts the hook 19 in the region 42, which is located between the hooks pivot point and the load 41 carried thereby. The hook 19 will be fixedly held in this position and will be unable to rotate its pivot point towards its position of stable equilibrium the load will therefore not slide off the hook 19 under this condition.

Whena trolley travels to a location 47 in the conveyor system at which it is desired to release the load, trip lever 43 is pivoted out of contact with hook 19 by pulling (either manually or by power) downwardly on handle 32 The trip lever 43 will be pivoted in the clockwise direction to thereby permit hook 19 to rotate about its pivot point. Thus free from constraint, hook 19 will rotate about its pivot point under the force of its load until it reaches its position of stable equilibrium whereat the load is released by sliding off hook 19. After release of the load, compression spring 46 will reset trip lever 43 to its original position and thereby force hook 19 to be reset to its fixed position described above.

The side plates prevent transverse wobble of the load by defining the space therebetween. The simple breakaway hook, which is easy to operate is set forth herein.

What is claimed is:

l. A break-away hook apparatus to selectively carry and discharge loads comprising:

first and second spaced side plates,

a hook rotatably mounted about a first pivot point between the first and second side plates. the position at which a load is carried by the hook being eccentric of the pivot point,

a trip lever rotatably mounted about a second pivotal axis between the first and second plates, the trip lever having a first position wherein it abuts the hook in the region between the first pivot point and a load carried by the hook to fix the position of the hook and prevent it from rotating about the first pivot point towards its position of stable equilibrium whereby the load is retained on the hook,

first means connected to the trip lever to actuate the trip lever about the second pivot point to a second position wherein the hook is enabled to rotate about the first pivot point under the force of a load carried thereby until a condition of stable equilibrium is reached whereat a load carried by the hook will be discharged by sliding off the hook.

2. The break-away hook apparatus recited in claim I further comprising:

second means connected to the trip lever to actuate it from its second to its first position after a load is discharged from the hook.

3. The break-away hook apparatus recited in claim 2 wherein the second means comprises a compression spring having one end secured to the trip lever, and its other end secured to support means mounted between the first and second side plates.

4. The break-away hook apparatus recited in claim 3 further comprising:

third means mounted between the side plates to define the angle of rotation of the hook about the first 4 pivot point.

5. The break-away hook apparatus recited in claim 4 wherein the first means comprises pull means connected to the trip lever.

6. The break-away hook apparatus recited in claim 5 wherein the apparatus is attached to a trolley in a conveyor system. and the pull means is actuable to discharge the load from the hook at a desired location in said conveyor system.

7. The breakaway hook apparatus recited in claim I further comprising:

second means mounted between the side plates to define the angle of rotation of the hook about the first pivot point.

8. The break-away hook apparatus recited in claim 7 further comprising:

third means connected to the trip lever to actuate it from its second to its first position after a load is discharged from the hook.

9. The break-away hook apparatus recited in claim 8 wherein the third means comprises a compression spring having one end secured to the trip lever and, its other end secured to support means mounted between the first and second side plates.

10. The break-away hook apparatus recited in claim 9 wherein the apparatus is attached to a trolley in a conveyor system, and the first means is actuable to discharge the load from the hook at a desired location is said conveyor system. 

1. A break-away hook apparatus to selectively carry and discharge loads comprising: first and second spaced side plates, a hook rotatably mounted about a first pivot point between the first and second siDe plates, the position at which a load is carried by the hook being eccentric of the pivot point, a trip lever rotatably mounted about a second pivotal axis between the first and second plates, the trip lever having a first position wherein it abuts the hook in the region between the first pivot point and a load carried by the hook to fix the position of the hook and prevent it from rotating about the first pivot point towards its position of stable equilibrium whereby the load is retained on the hook, first means connected to the trip lever to actuate the trip lever about the second pivot point to a second position wherein the hook is enabled to rotate about the first pivot point under the force of a load carried thereby until a condition of stable equilibrium is reached whereat a load carried by the hook will be discharged by sliding off the hook.
 2. The break-away hook apparatus recited in claim 1 further comprising: second means connected to the trip lever to actuate it from its second to its first position after a load is discharged from the hook.
 3. The break-away hook apparatus recited in claim 2 wherein the second means comprises a compression spring having one end secured to the trip lever, and its other end secured to support means mounted between the first and second side plates.
 4. The break-away hook apparatus recited in claim 3 further comprising: third means mounted between the side plates to define the angle of rotation of the hook about the first pivot point.
 5. The break-away hook apparatus recited in claim 4 wherein the first means comprises pull means connected to the trip lever.
 6. The break-away hook apparatus recited in claim 5 wherein the apparatus is attached to a trolley in a conveyor system, and the pull means is actuable to discharge the load from the hook at a desired location in said conveyor system.
 7. The break-away hook apparatus recited in claim 1 further comprising: second means mounted between the side plates to define the angle of rotation of the hook about the first pivot point.
 8. The break-away hook apparatus recited in claim 7 further comprising: third means connected to the trip lever to actuate it from its second to its first position after a load is discharged from the hook.
 9. The break-away hook apparatus recited in claim 8 wherein the third means comprises a compression spring having one end secured to the trip lever and, its other end secured to support means mounted between the first and second side plates.
 10. The break-away hook apparatus recited in claim 9 wherein the apparatus is attached to a trolley in a conveyor system, and the first means is actuable to discharge the load from the hook at a desired location is said conveyor system. 